Materials Data on Mg2Co2O5 by Materials Project

Abstract

Mg2Co2O5 is Aluminum carbonitride-like structured and crystallizes in the orthorhombic Ima2 space group. The structure is three-dimensional. Mg2+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Mg–O bond distances ranging from 2.02–2.26 Å. There are two inequivalent Co3+ sites. In the first Co3+ site, Co3+ is bonded to six O2- atoms to form CoO6 octahedra that share corners with four equivalent CoO6 octahedra and corners with two equivalent CoO4 tetrahedra. The corner-sharing octahedral tilt angles are 35°. There is two shorter (1.92 Å) and four longer (1.95 Å) Co–O bond length. In the second Co3+ site, Co3+ is bonded to four O2- atoms to form CoO4 tetrahedra that share corners with two equivalent CoO6 octahedra and corners with two equivalent CoO4 tetrahedra. The corner-sharing octahedral tilt angles are 51°. There are a spread of Co–O bond distances ranging from 1.84–1.98 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted see-saw-like geometry to two equivalent Mg2+ and two equivalent Co3+ atoms. In the second O2- site, O2- is bonded to two equivalent Mg2+ and two Co3+ atoms to form distorted corner-sharing OMg2Co2 tetrahedra. In the third O2- site, O2- is bonded to two equivalent Mg2+ and two equivalent Co3+ atoms to form distorted corner-sharing OMg2Co2 tetrahedra.